1. Field of the Invention:
The present invention relates to a coin wrapping machine, and more particularly to a guide device for facilitating smooth guide of wrapping paper when the wrapping paper is wrapped around an accumulated column of coins.
In a coin wrapping machine, a pre-set number of coins is stacked to form a column of coins and then a sheet of wrapping paper or other wrapping sheet, such as plastic sheet, is wrapped around the outer periphery of the coin column. The wrapping sheet is fed in a form of continuous web having a width larger than the height of the accumulated column of coins, so that marginal cylindrical portions formed of the wrapping sheet extend beyond the upper and lower end faces of the coin column. These extending cylindrical portions are then crimped and caulked to obtain a wrapped coin column. Generally, several species of coins are handled in the same coin wrapping machine. Therefore, the coin wrapping machine shall be adapted to handle a variety of coin species. The present invention is directed to a device for guiding a web of wrapping sheet smoothly in wrapping operation whatever species of coins are handled to be wrapped by the machine.
2. Prior Art:
A typical coin wrapping machine known in the art is shown in FIG. 1, wherein three wrapper rollers 1, 2 and 3 are provided and rotated by driving means, not shown. The ends of the rollers 1, 2 and 3 are rotatably carried by carrier links 4, 5 and 6, respectively, and these carrier links can be swung to allow the wrapping rollers 1, 2 and 3 to engage with or disengage from the outer peripheral portions of the coin column a. It should be noted here that another similar set of carrier links carries the lower ends of the wrapping rollers 1, 2 and 3 although only the upper set of carrier links 4, 5 and 6 is shown in the Figure for clarity. A guide plate 7 for guiding the leading end of the web of wrapping sheet along the periphery of the coin column a is rotatably mounted to one of the rollers, for example the roller 1 as shown. Attached to the guide plate 7 is an arm 8 which is pivoted to one end of a link arm 9. The other end of the link arm 9 is connected via a rod to another link arm 10' which carries a bar having the free end provided with a crimping claw 10. The link arm 10' can be pivoted about a shaft 11 to position the crimping claw 10 over or out of the coin column a clamped by the wrapping rollers 1, 2 and 3. When the bar carrying the crimping claw 10 is desired to move to the operating position, the guide plate 7 must be retracted to the position at which the guide plate 7 is out of the sheet guiding position. For this purpose, the arm 8 is swung through the link arm 9 to put the guide plate 7 out of the way of the moving pawl 10. Reference numeral 13 designates a support cylinder for receiving and holding the coin column a from an accumulator tube, not shown. The coin column a is lowered to the position surrounded by the wrapping rollers 1, 2 and 3 while being held by the support cylinder 13, and then engaged with three rollers at a position centrally of the latter. The wrapping rollers are then rotated to rotate the coin column and to wrap the wrapping sheet around the coin column.
In the aforementioned wrapping machine of prior art technology, the shape and size of the sheet guide plate 7 is designed such that it can be positioned to handle the smallest coins. This is because the guide edge of the plate 7 tends to contact with the periphery of another roller, for example roller 2, when a coin column of larger diameter is handled, if the shape and size thereof is designed to accommodate to the coin column of larger diameter. As a result, when a coin column of larger diameter is handled by the prior art device of the aforementioned type, a gap of appreciable dimensions (for instance, as denoted by b in FIG. 5) is formed between the guide edge of the plate 7 and the periphery of the coin column. The leading end of the web of wrapping sheet extending over this gap is not guided by any member in operation of the prior art device, so that the leading end of the web tends to be mis-led so as to be deviated from the designed vertical position to result in a helically wrapped condition or tends to be folded, which at a later time would cause slack in the wrapping sheet wound around the coin column. The tendency of forming the helically wrapped cylinder of wrapping sheet, as aforementioned, is particularly disadvantageous in that the marginal ends of the cylinder of wrapping sheet projecting beyond the ends of the coin column bring a considerable difficulty in the subsequent crimping operation.